The field of the invention relates generally to combustors for turbine engines, and more particularly, to dual mode combustors for rotating detonation engines.
In rotating detonation engines and, more specifically, in rotating detonation combustors, a mixture of fuel and an oxidizer is ignited such that combustion products are formed. For example, the combustion process begins when the fuel-oxidizer mixture in a tube or a pipe structure is ignited via a spark or another suitable ignition source to generate a compression wave. The compression wave is followed by a chemical reaction that transitions the compression wave to a detonation wave. The detonation wave enters a combustion chamber of the rotating detonation combustor and travels along the combustion chamber. Air and fuel are separately fed into the rotating detonation combustion chamber and are consumed by the detonation wave. As the detonation wave consumes air and fuel, combustion products traveling along the combustion chamber accelerate and are discharged from the combustion chamber.
However, during at least some stages of operation such as start-up and partial load stages, conditions are not sufficient to sustain a rotating detonation combustion process. At such combustor operating conditions, the pressure and/or temperature within the combustion chamber are not sufficient to sustain the constant volume combustion of the rotating detonation combustion process. Accordingly, during at least some stages of operation, such as during start-up, rotating detonation combustion does not occur or occurs at less than the ideal efficiency.